Adjustable suspension supports are used for example in hospitals where a support is suspended from the ceiling to carry plasma bottles for intravenous injections. An example of such a support is shown in U.S. Pat. No. 3,191,904 issued June 29, 1965 to A. D. Karapita. Because of the difficulty in adjusting the support rotationally and upwardly it had previously been proposed to use vacuum means with a suspension support, as disclosed in U.S. Pat. No. 4,073,456 issued Feb. 14, 1978 to A. D. Karapita. Since then an improved support, eliminating the need for a vacuum source, has been disclosed in U.S. Pat. No. 4,374,581 issued Feb. 22, 1983 in the name of A. D. Karapita.
The problem with the device disclosed in U.S. Pat. No. 4,374,581 is that the release of the suspended object could impose a burden of unexpected weight on the operator. Also, the mechanism could be released relatively easily by a patient, which could be especially dangerous in the case of a child.
It is an object of the present invention to provide an improved suspension unit which requires the imposition of an upward force to release it for vertical adjustment.